Casaubon's Book

It isn’t Waste if You Do It Right

A few days ago, the New York Times ran an article about the problem of manure handling on large farms. . From the title “Down on the Farm, an Endless Cycle of Waste,” which completely misses the point that manure is not “waste” to the end, the article failed to ask any of the really pertinent questions raised by really large scale industrial agriculture and its chronic problems with manure handling.

In function it is something like a Zamboni, but one that has crossed over to the dark side. This is no hockey rink, and it’s not loose ice being scraped up. It’s cow manure.

Lots of cow manure. A typical lactating Holstein produces about 150 pounds of waste — by weight, about two-thirds wet feces, one-third urine — each day. Mr. Volleman has 3,000 lactating Holsteins and another 1,000 that are temporarily “dry.” Do the math: his Wildcat Dairy produces about 200 million pounds of manure every year.

Proper handling of this material is one of the most important tasks faced by a dairy operator, or by a cattle feedlot owner, hog producer or other farmer with large numbers of livestock. Manure has to be handled in an environmentally acceptable way and at an acceptable cost. In most cases, that means using it, fresh or composted, as fertilizer. “It’s a great resource, if used properly,” said Saqib Mukhtar, an associate professor of biological and agricultural engineering at Texas A & M University and an expert on what is politely called manure management.

But as the increasing incidence of environmental and health problems linked to agriculture makes clear, when manure is mismanaged the nutrients in it can foul streams, lakes and aquifers; the pathogens in it can contaminate food products; and the gases it produces, including ammonia, methane and bad-smelling volatile compounds, can upset neighbors and pollute the atmosphere.

Even with best practices, manure can cause environmental headaches. So researchers are working on ways to improve its handling, to modify the nutrients in it and to develop alternative uses.

I’m so glad we have researchers working day and night to figure out how to manage 200 million lbs of cow manure, to make it less toxic, and to deal with the environmental “headaches” that even the “best practices” can cause. If it were me, not being a researcher, I would tend to think that those research dollars could be spent elsewhere, maybe on breeding a cow with antennae or something really cool, because I know the magic trick to making manure not an a massive environmental hazard that is risky even with the “best practices.” After extensive research (and I’d really like some company to pay me some money for this, since I obviously worked hard at figuring it out, and am clearly a genius), I’ve figured out how to reduce the manure handling hazard, and convert it from “waste” to something extremely wonderful and useful (although I can’t make it smell like lavender.”

Don’t have 4,000 cow dairies. Don’t put more cows in one place that make since given the land’s capacity to absorb the manure. Don’t set up a system that needs a manure lagoon and a shit-scraping zamboni running 24 hours a day. Don’t have so many cows that manure functions as “waste” because it isn’t – it is fertilizer. But it is only a fertilizer if you can return it to local land – as the article points out, it doesn’t make sense to truck manures long distances – and that means a smaller number of cows in more dairies.

But the Times article doesn’t consider this. The assumption is that the manure lagoons and the practices that surround that kind of quantity of manure are inevitable:

With nitrogen, the problem is usually not that there is too much, but that much of it is eventually lost from the manure in the form of gaseous ammonia. The bacteria in feces contain an enzyme, urease, that breaks down urea in urine into carbon dioxide and ammonia. As with phosphorous, diet can affect the amount of nitrogen retained in the manure. As corn-based ethanol production has increased in the United States, many dairies and feedlots now give their animals a large amount of so-called distillers’ grains, the waste corn after fermentation, which are plentiful and cheap. A recent study of feedlots in the Texas Panhandle, by scientists with the United States Department of Agriculture, showed that feeding a diet high in distillers’ grains produced significantly higher ammonia emissions from the manure.

Emissions problems can also be reduced by changing how the manure is applied. Tilling the soil immediately after application of dried manure can help reduce odors, Dr. Mukhtar said. And if manure is directly injected into the soil in slurry form, Dr. Burns said, the ammonia can better bind with the soil. Currently in Iowa, a major hog-producing state, about 80 percent of hog manure is injected.

When it comes to the liquid end of things, there are delicate balances to be maintained as well.

Regulations vary by state, but in Texas, manure lagoons have to be big enough to handle a severe rainstorm of the type that occurs, on average, only once every quarter-century. The danger is that an overflow from a lagoon, with its high concentration of organic matter and nutrients, could eventually reach a creek or some other body of water and kill fish.

Ok, in Texas, you have to be big enough to handl the 25 year storm. But wait a minute. What happens when the 50 year storm happens? Or the 100 year storm? Or for that matter, what happens when climate change ups the rate of those storms?

Even without those storms, we have ample research to suggest that manure lagoons are not the hottest idea on the planet. For example, not all areas that have lagoons should have them – when groundwater runs near them, you get contamination anyway There have been more than 200 significant manure spills and leaks from lagoons in just the last four years, many with substantial environmental costs, including one in New York in 2005 about an hour from me that killed 375,000 fish in the Black River and contaminated local water tables.

The truth is that this much animal manure cannot be handled safely over the long term – all of our best attempts to regulate and control have not stopped CAFO animal manures from contaminating water tables, rivers, lakes and streams. Moreover, if you imagine that we don’t have all the fossil fuels we could ever want, or that we shouldn’t burn them these agricultural models are a complete disaster. Putting 4 or 5 or 6 thousand cows in one place means that the farm will always be profoundly dependent on energy intensive equipment like the manure-zamboni. They will always be overwhelmed by the fact that their land can’t absorb all the manure. A single shortage or extended outage is a disaster.

And we can’t afford to waste our manures. The article above cheerfully reports you can reduce odor by tilling the manure in – but of course, besides being resource intensive, this means that carbon held by the soil is being released, rather than contained. We need to reduce tillage, not increase it, or begin it on pastures and hayfields, which are environmentally positive in large part because they are not being tilled. Besides producing a shitload (forgive me) of methane, they are also upping carbon release this way.

We also can’t afford to waste our manures because we need the fertilizers. We have already seen wild fluctuations in fertilizer costs in the last few years, resulting in farmers struggling to afford to buy enough. Potash prices rose dramatically in 2008-2009, while the cost of artificial nitrogen and rock phosphates have also fluctuated. Farmers can’t afford to ignore local resources. But, as the article points out, it doesn’t make sense to truck manure more than 10 miles.

But again, that’s the magic of my solution. Instead of 1 4,000 cow dairy, let’s say you have 40 100 cow dairies. Guess what? They can’t all exist on exactly the same land – so you spread that manure out. Most farms that raise their cows on pasture can pretty much handle the manure produced by 100 cows, assuming they have agricultural neighbors to share with. Better yet, what about 100 40 cow dairies? Your average farm that can support 40 cows can completely handle their manure. No lagoons, just composting piles and spreading on fields – and a lot fewer piles, because, of course, if the cows actually go outside and eat grass, they are spreading their own manure.

In my own region of the country, thousands of dairy farms have gone out of business. Did those farmers just hate their work and voluntarily give up the ghost? Nope – I know these guys and they are my neighbors. My town had twice as many dairies 10 years ago, and twice as many as that 20 years ago. It has been a long and painful process of agonizing attrition, farmers hanging on just one more year, trying to make it work as they are undercut by people with 4,000 cows and with an agricultural system that would rather invest money in research to make the poop less toxic than simply recognize that none of us are served by the consolidation of dairy farming. It would haven’t taken a massive shift in subsidies and practices to keep those guys in business, and I know 10 who would go back in a heartbeat, if they could be promised something other than another disaster. These are guys who love their cows, who know their 60 cows, who wanted nothing more than to keep getting up at 4 in the morning for the rest of their lives so that you could drink a glass of milk.

Sharon

Comments

  1. #1 Sara: farming in northern rural Alabama
    January 3, 2010

    Coincidentally or not, NPR ran a story on it’s website that’s about a small organic dairy farm. http://www.npr.org/templates/story/story.php?storyId=122119570

    Sara

  2. #2 derek
    January 3, 2010

    The problems are “inevitable” once you assume capitalism. The result is enterprises that pollute their environment, waste resources, and force your neighbors out of a livelihood they were dedicated to. But they give a good return to the stockholders.

    I can sympathize with the NYT for not wanting to mention the elephant (manure) in the middle of the room.

  3. #3 Greenpa
    January 3, 2010

    REALLY, Sharon. There you go again, being so unreasonable.

    Honestly. You truly expect business/systems/government to be run in a rational fashion?

    How foolish can you be. :-)

  4. #4 Stephen B
    January 3, 2010

    Wow, if I ever had any doubt that the end of the Oil Age absolutely dooms large, industrial agriculture (especially animal agriculture), one look through the photo slide show accompanying that NYT article removed every last bit of it.

    At 200 Million pounds a year of manure, and 60K lbs. per 18 wheeled dump truck load, that’s almost 10 truckloads each and every day, just to haul the poop to the intermediate staging point before spreading.

  5. #5 Brad K.
    January 3, 2010

    Here I was thinking, you know, cow dung, dried, does burn in a rocket stove. I recall an episode of whichever show had Brian Keith and a couple twins and a butler, touting genuine marmalade “roasted over an ox dung fire”.

    Then I remembered – Paul Harvey (I do remember Mr. Harvey) reported on a company making electric generation units, that fermented manure and burned the resulting methane to produce electricity. As I recall the units were about $1million, thus more suitable for larger operations. I suppose a variant might use methane to enable a flash-dry operation, and package the dry matter as “BS Briquets”. Useful for election day barbecues, no doubt. Maybe this version could be adapted to smaller operations.

    As for 100 cow dairies – Dad milked 8 to 12 cows, mostly manually. The dairy didn’t pay enough to make much money (Mom figured they lost $2 in income the year after Dad quit milking) but we had milk and occasionally cream. A dozen cows, on a modest 160 acre farm, left little extra time. I suspect 25 cows or more will be an industrial farm, with most of the same issues as the 4000 farm. With a smaller operation you can rely on silage, on pasture, for most of the feed and good use for the manure. And the amount might still be credibly composted rather than spread raw. Although, as I recall pulling a “spread it high and wide” spreader full makes one *very* aware of which direction the wind is from. I would set the target more appropriate to a mixed product family farm operation, with something less that 100 cows.

  6. #6 Jerry
    January 3, 2010

    Sharon,
    I’ve always had the perfect solution to 4000 cow dairies, make every dairy farmer milk their own cows just as I do. You would be surprised how many large herds would stop milking. I also believe that large herds require so much more energy of all types especially to grow large amounts of forage that they will not be able to compete with a small farm that rotationally graze their cows. In time we will go back to one hundred forty cow herds.

  7. #7 vera
    January 3, 2010

    Eh… this reminds me of a post Ran Prieur made recently… something about how if the system had its druthers, it would destroy clouds, make artificial ones at great cost and heroic effort, and have them rain at the touch of a button. Then vast armies of people would be employed to keep them going, while another vast army of researchers would make a living trying to figure out all the “headaches” even “best artifical rain practices” would bring us. And a small group of people would hugely profit by all this. Insanity rules… by design!

    What I would love to see somewhere is how exactly the economic patterns are set up to muddle things up like this. It takes a lot of directed effort to succeed at killing dairy farming upstate NY!

  8. #8 Stoneleigh
    January 3, 2010

    As it happens, my day job is in exactly this field. It’s amazing what you can do with anaerobic digestion – create a largely odour-free and pathogen-free fertilizer while reclaiming the energy fraction as both heat and power. Energy throughput is vastly reduced, as is water pollution, by both nutrient run-off and pathogens.

    Digestate, unlike raw manure, will not clog plant pores and inhibit transpiration, and it does not contain acids that can burn leaves. The nutrients are in a form readily available to plants, and odourless digestate can be stored until plants need fertilizer.

    Greenhouse gas emission are greatly reduced where manure is digested and the methane fraction removed, rather than stored in open pits where methane (a potent greenhouse gas) simply escapes to the atmosphere.

    The combination of manure with high-energy off-farm organic waste streams is also beneficial. While manure is not readily transportable and must be digested in situ, high-energy off-farm wastes can be transported, and are much more useful in a farm-based digester than they would be in a landfill.

    Anaerobic digestion works well in conjunction with composting to produce carbon-enriching soil conditioner as well.

    NYT really missed the boat on this one :)

  9. #9 Thisbe
    January 3, 2010

    It is (with certainty) governmental agricultural policy creating artificial economies of scale for giant industrial dairies while allowing them to ignore (rather than pay for) real environmental and social costs that leads to small dairies going out of business.

    The answer lies in changing policy, which is decidedly unglamorous as well as unlikely to occur anytime soon – because who has more money, you and I or the corn lobby?

  10. #10 Jen
    January 3, 2010

    I’m trying to remember where I just read an article about the dead zones in the Chesapeake Bay and how they’ve been trying to clean it up FOREVER, but due to all of the manure run-off from farms they can’t. Good article along the same vein.

  11. #11 Greenpa
    January 3, 2010

    Good info, Stonleigh;some stuff I didn’t know there.

    There is also Joel Salatin’s approach, which I’m thinking more about. Basically, via intensive management, he turns cattle into a fresh rotational paddock for about 3 days (I think!) during which time they go through the lush stuff, and drop a lot of poop. Then he moves the cows off.

    And waits a precise amount of time; something like another 4 days, I think- to the point where the cow pats are full of fat, nearly mature fly larvae. Then he brings his egg tractor into the paddock, and his free-range laying hens go to work. They eat fly larvae like crazy- and also scratch the pats completely apart; so you don’t wind up with a lush green spot which the cows won’t graze. Also drastically cuts down the flies; I’ve seen it.

    Turning the cow pats into chicken manure; N as uric acid; which will zip right back into the plants as available N.

    I like this way; in terms of field management; since all nutrients in the waste stay right there, including the mineral ash.

    You don’t get electricity this way- just an awful lot of food; and good fields; and no polluted water. And you don’t have to go pick up after the cows…

  12. #12 tony lovell
    January 3, 2010

    Imagine if we had a process to remove billions of tonnes of CO2 from the atmosphere safely, quickly and cost-effectively – while at the same time reversing desertification, boosting biodiversity, enhancing global food security and improving the lives of hundreds of millions of people in rural and regional areas around our planet?

    We do – it’s called changed grazing management and soil carbon.

    Please take a look at the presentations on http://www.soilcarbon.com.au/ to learn more.

  13. #13 Crunchy Chicken
    January 3, 2010

    Greenpa – I believe you are completely correct (not sure about the spacing/time of rotations though) about Salatin’s approach. I know he also lets his chickens hang out under the rabbit cages for the same reason – they scratch the manure into oblivion. I think more and more farms are following his rotational technique, which makes me very happy.

    The trick is to find someone local who does the same thing. Fortunately, we’ve found a farmer or two in the western WA area that does. Of course, the cost is more than conventional chicken. It’s $5.99/lb, so you’ll pay about $25 for a smalllish chicken versus $12 for straight up organic and pennies on the dollar for factory farmed. But, we are paying the true costs of raising these animals versus the highly subsidized, corn-fed, tortured chickens. Same deal with beef.

  14. #14 EJ
    January 4, 2010

    I think it was Wendel Berry who said that modern agriculture takes a old solution (manure) and turns it into two new problems (farm fertility and waste/pollution).

  15. Greenpa, the cows and meat chickens are moved every day, and the laying hens every 3 to 4 days depending on if they are in the electric fence or the free-range Eggmobile.

    Cows and chickens go inside for the winter months to allow the land to rest.

  16. #16 Daniel from Sweden
    January 13, 2010

    Incidentally, I wrote a longer text about how it is inevitable that rationalization in its current form will wither during the first half of this century and how we will have smaller and more numerous slaughterhouses, bakeries, breweries and dairies again in a forseeable future – http://www.energybulletin.net/51140